Fluid line connection



Aug. 16, 1949. s. WILTSE 2,479,447

FLUID LINE CONNECTION Filed Feb. 7, 1945 U I g Q INVENTOR.

' q o N 4 N suumea WILTSE 4 (9 By g 5 Md/ '2 ATTORNEYS Patented Au 16, 1949 tsl umneizlwil tse ljetrcit, m n assiiennnm titres Q al'.Corporatibh Detr0it;.Mich2 afclj i 'l j ti .of Michigam' .4 A ueatibnnbm 'z, mmswtnqamsem v s Claii'nis.

This invention; relates-generally to connections between tubingand fittin s therefor, and refers more particularly toa fluid type connection. between a high pressure hydraulic tube:and a suitable-fitting therefor. i

- Heretofore in fluidline-connecti ons, a: resilient sealing ring or gasket has: been mounted in opposed annular groqv-esi intthet tubing and encircling fitting therefor; to prevent relative endwise movement betweenmthe: tubing and fitting, and clearance hasbeen provided between the tubing and fitting to: permit-relative tilting movementbetweenthe parts. Ordinarily the tubing is ductile and doesnot return; to its original shape, state, orconditicn af ten the; annular groove aforesaid is formed therein. However, the sealing ringis usually formedloff rubber or rub ber compositionand: therefore has; a high recovery' rate. In" tact it? has been found that this resilient ring is adapted to absorb any impact loads or forces, applied ..,thereto. froni theifiuid in the tubing vianthe outer wall of. thegroove in which the ring mounted} and. to reactl'ilie, a; spring under compressionand' thereby repeatedly deform and produce a hammer liker action against the inner wall of? the annular groove in the tubing te'ndin'g tolflattenthe same. Consequently, when the tubing of} the connection mentioned is employed" as a high pressure hydraulic line, the-impactlbadson forces ofthe hydraulic ifl'uidl against" the inner Walli' of the annular groove. in the tubing cause the resilient ring in the groove tblhe repeatedly deformedfendwise oi the tube against thefinner wall of said roove and thereby to, hammer db'wn and; pro gressively deform the am jcjentiin'n'er end portion or the tubing to'a mal r"dia7meter',, permitting th'etubingto sup-out oft'h'e fitt ng.

Therefore, one of the: essential Q f 'c't's "of the present invention is to" provide a fl linecbn, nection having means, preferably in the form of a stop" or abutment for the resilienti'ring, for erfectively preventing any hammer-like action of theiresilientflri'ng being ilmpartedl tdt'hei inner side wallv of the annular groove in'fthe tubing. Another object is to prmiidea fi'uid line connection wherein thesto'p. or abutment. is preferahly formed of metalfancl' located at' the "inner side of the resilient. ring. for sealing engagement with the inner side; wallsv of theopposed annular grqoveszin the fitting; and tube,

Another obj ect; is to providea,- fluid line connection wherein the stop or abutment; is-zpreferably in the form of afemileior. the tubea-ndgis ad pted; to be ri-eadilmleev dr;there n n tend m "provide a fihid line' con- .v w th t operatihg sedtion'si o'f'th 'fltting 'andfjthe. inter-- mediate r g: "Whenisuch sections ofthe l sewn: resi fln e r i t to a tl'i i bk'el" Wailld' time" WYflch'" would be "impractical with thistype omitting.

A ri'qther bbject is to provide a fluid line connec i n i si imflef tees ii' 't b m- 25 1 n efficient vi v)" I. i, ,',v.-, i.

Other, injects, advantagestandfnovei details a ,7 t bnfi si event bw e made r th se br m oce d peciaily when Chiisifcteifefiiih cbhnectioh with the 1; 1 ne t line showing tne' tutingfiif 'ite miner meant-tu tepreferably comprises two sections II and I2 respectively. The section II may be a hydraulic brake housing, pump casing, or any other suitable element of a hydraulic or fluid line system, and preferably has a fluid passage I3 provided at the mouth thereof with stepped enlargements I4 and I5 respectively. Such section II is also provided between the stepped enlargements I4 andaI 5 with an inclined or bevelled wall or shoulder I6. The

other section I2 of the fitting has a polygonal body I7 adapted to abut the section II and provided at one side with an axially extending tubular projection or nipple portion I8 adapted to extend within the outer enlargement I5 of the section II of the fitting. Such tubular'projection' I8 is provided adjacent the body I! with an exteriorly threaded section I9 that is engageable with an interiorly threaded portion of the outer enlargement I5 of the section II when the parts are assembled, and is provided at its free end with a surface 2I that is' oppositely inclined relative to the inclined surface I6 of the section II. Preferably these inclined surfaces I6 and 2| converge toward theouter enlargement I5 of the section II soas to squeeze the resilient ring 0 against the tubing A when the parts are assembled.-.

The resilient sealingring C is preferably made of rubber, synthetic rubber, or rubber composition, preferablyimpervious to gasoline and oil and having advantageous characteristics for the purposes for which it is used. Preferably opposite sides 22 and 23 respectively of, the ring C are inclinedtoward each other from the central opening24 to the'periphery 25 of the ring; however, any other suitabl configuration may be employed, as desired.

The ferrule D is preferably L-shaped ingcross section and is preferably .0022" to .0028 thick.

It is preferably formed from cold rolled half hard I steel.

In use, the tubing A is initially of uniform diameter throughout its length as illustrated in Figure 3. Thesectio'n. I2 of the fitting, resilient ring C,'and metal ferrule D ar then sleeved one after the other upon the tubin A as illustrated in Figure 3. The end portion of the tubing is then inserted int'ofthe inner enlargement I I of the sectionv I I of the fitting so that the ferrule D will abut the inclined surface It of said section, the resilient ring 0 will be between. the inclined surfaces I6 and 2| of the sections II and I2 of the fitting, and the exteriorly threaded portion IQ of the section I2 will belengaged with the intericrly threaded portion 20 of the section H. Then the polygonal body I! of thesection I2 is turned by a suitable'tool (not shown) to cause the sections I I and I2 to be tightened together so that the resilient rin 0, ferrule D, and tubing III will be simultaneously. deformed as illustrated in Figure 1. V 7

When the parts are in the position illustrated in Figure l, the tubing A will have an annular concave indentation or groove 3| in opposed relation to an annular groove 32 that is formed by the oppositely inclined surfaces I6 and 2| and outer enlargement I5, and the resilient ring C will fill completely and bear firmly against the walls of the opposed annular grooves SI and 32 in the tube and fitting to provide a fluid tight seal therebetween. In this connection it will be noted that the opposed annular grooves 3| and 32 in the tubing and fitting cooperate with the resilient ring C to prevent endwise movement of the tubing A relative to the fitting B. Also it will Cir be noted that the surface 33 of the resilient ring C engaging the concave groove 3| in the tubing conforms in curvature to said concave groove 3I and that there is sufficient clearance at 34, 35, and 36 respectively between the tubing A and fitting B to permit angular or tilting movement of the tubing relative to the fitting, or vice versa. In this connection it should be appreciated that the surfaces of the resilient ring C adhere or remain firmly in contact with the surfaces of the opposed grooves 3I and 32 so that the angular or tilting movement mentioned is taken up within the resilient body of the sealin ring 0. Moreover the clearancebetween the tube A and fitting adjacent opposite walls of the opposed grooves therein is insufficient to permit extrusion of the sealing ring C from the fitting endwise of the tube A. The deformed ferrule D is now substantially V shape in cross section. By referring to Figure 1 it will be noted that the apex D of the ferrule is in registration with the clearance 34 between the tube A and section II of the fitting and the legs D and D of said ferrule overlap and have surface to surface sealing engagement with the inner walls 3'1! and 38 respectively of the opposed grooves 3I and 32. Actually this ferrule D serves as an interceptor for the impact loads of the hydraulic fluid as well as a stop or abutment for the deformed sealin ring C and distributes over a wider surface the impact loads imparted to the sealing ring C from the fluid in the tubing A via the inner side wall 31 of the annular groove 3i in the tubing. If such ferrule D were omitted, the reacting force of the resilient material of the sealing ring C, after absorbing the energy of the impact loads of the hydraulic fluid via the inner wall 3'! of the annular groove 3 I, would cause the ring C to return like a sprin against the inner wall 31 of the annular groove 3I in the tubin to deform the same. Successive action of this type would be in hammer-like fashion, hence the inner end portion 30 of the tubing would be progressively deformed to a smaller diameter, permitting the tubing to slip out of the fitting. However, the presence of the ferrule D between the sealing ring 0 and inner walls 31 and ,38 of the opposed grooves 31! and 32 effectively prevents such destructive action of the resilient sealing ring C. Consequently the ferrule D serves as a guard for the end. portion 39 of the tube while permitting relative tilting movement betweenthe tube and fitting.

What I claim as my invention is: 1. In a fluid line connection of the class .de

scribed, a thin walled tube, afittin encircling said tube with clearance therebetween to permit tilting of the tube relative to the fitting or vice versa, a fluid-tight seal between the tube and fitting including a ring of resilient material sleeved on said tube within the fitting and a metal ferrule sleeved on said tube beside the ring within said fitting, said tube and fitting having opposed annular grooves receivin and cooperating with the ring and ferrule to prevent endwise movement of the tube relative to the fittin while permitting the tilting movement aforesaid, said ring and ferrule collectively filling completely and bear-= ing firmly against the walls of the opposed annular grooves in the tube and fitting so that the tilting action aforesaid istaken up within the resilient body of the ring, opposite Walls of the groove in the fitting bein relatively movable and coacting to maintain the firm engagement aforesaid of the ring and ferrule with the walls of the opposed grooves respectively in the tube and fitting, the clearance between the tube and fitting swam? V being in registration withjthe clearance: afore said between the tube and fittingtandthe -legszo'f the V overlapioi-ng and ha'rvi'rigsurface tosurface sealing: engagmentiwith: the inner "sidewalls respectively of said: opposedannular grooves aforesaid, the-leg ol the' V' in --contact with the sidewall" of thefgrooveinrthafittingr-being ofless outside diameter than 'thedhimeter of -the bottom for the groove, whereby said ferruleform'siavprotctin'g barrier'betweerrthe inner side o'f' said ring and the fluid irr-said clearance and-'constitutes-a stop or abutment for Saidwing? toprevent any hammer-like action-of said-ring created by incpact loads of fluid in the Wbewf-YOIYI being imparted to the inner sidewalkof the annular groove in said tube and has sliding contact with the said side wall of'thegrooVe-iir-said fitting.

2'. In a fluidline connection ofthe class described, athin" Walled "tube, :a fitting encircling said tube with clearance =therebetween to permit tilting of the tube relative to the fitting'prvice versa, afluid' tightdeal between the tube and fitting including a ring of resilient material sleeved on said' tub Within the fittin and a t in me al e re e s eev d ase e b e th ring within said fitting, said tube fitting having opposedannular grooves'rce mg and er)"- operating witlr ti i ring ana ferrule-to prevent endwise movement of the ;tube relative to, the fitting while Permitting the tilting movement aforesaid,- said ring and ferrule collectively filling completely, and bearing firmlyagainstqthe walls ,of the opposed annular iQovese-in the tubeand fitting so that the tilting action aforesaid is taken up within the resilient body of the ring, opposite walls of the groove in the fitting being relatively movable and coacting to maintain the firm engagement aforesaid of the ring and ferrule with the walls of the opposed grooves respectively in the tube and fitting, the clearance between the tube and fitting adjacent opposite walls of the grooves therein being insuflicient to permit extrusion of the rin from the fitting endwise of the tube, said ferrule spanning the space between the inner side walls respectively of said opposed annular grooves, a portion of said ferrule being in registration with the clearance aforesaid between the tube and fitting and other portions of said ferrule overlapping and having surface to surface sealing engagement with the inner side walls respectively of said opposed annular grooves aforesaid, whereby said ferrule forms a protecting barrier between the inner side of said ring and the fluid in said clearance and constitutes a stop or abutment for said ring to prevent any hammerlike action of said ring created by impact loads of fluid in the tube from bein imparted to the inner side wall of the annular groove in said tube.

3. In a fluid line connection of the class described, a thin walled tube, a fitting encircling the tube with clearance therebetween to permit tilting of the tube relative to the fitting or vice versa, a fluid-tight seal between the tube and fitting ineluding a ring of resilient material sleeved on the tube within the fitting and a thin metal ferrule sleeved on said tube beside said ring, said tube and fitting having opposed annular grooves receiving and cooperating with the ring and ferrule to'preventendwise'movement ofthe-tube-relative to the fitting while: permitting the tilting move ment aforesaid"; opposite wane of the groove in the fitting' being relatively movable and co'act ing to maintain the resilient" sealing ring and ferrule firmly againstthe walls 'of the opposed groovesrespectively in the tube and fitting so'tha-t the ring and ferrule areeheld in sealing engagement with" the walls of the opposed grooves respectively in said tube and fitting during the tilting movement aforesaid said ferrulebeing substantia'lly' V shape in cross section-end spanning the space betweenthe inner" sidewalls respectively of said' opposed annular grooves, the apex of the V being inregistration with the: clearance aforesaid between the tube'and' fitting and thelegs of the V overlapping and havingsurfaceyto surface sealin engagementwith the inner sidewallswre spectively of said opposed annular grooves whereby? said ferrule forms" a protecting barrier between the'inner" side of said ring and the "fluid in "said clearance and constitutes a stop or abut ment for said ring to prevent anyhammer-like action of said ring created by impact loads of fluid in the tube from being imparted to the inner side wall of the'annular'groovein said tube;

.4. In a fluid line connection of the class described, a tubeja fitting encircling the tube with clearance "therebetweerr to prmit tilting of the tube-relative to the fitting or vi'ceversa, enumtight seal between the tube and fitting-includi-n'g' ring of resilient material sleeved: on the tube within the fitting and a--ferrule sleeved on said tube beside said ring, said tuba -and fitting having opposed annular grooves receiving and cooperating with the ring and" ferrule t'o rvent endwise movement ofthe tube relative to" the fitting "wane permitting the" tilting movement aforesaid, opposite walls of the groove in the fitting being relatively movablean'd coacting to :fnaintain the resilient sealing fingrahdi-ferrul firmly against the walls of the opposed grooves respectively in the tube and fitting so that the ring and ferrule are held in sealing engagement with the walls of the opposed groovesrespectively in said tube and fitting during the tilting movement aforesaid, said ferrule spanning the space between the inner side walls respectively of said opposed annular grooves, a portion of said ferrule being in registration with the clearance aforesaid between the tube and fitting, and other portions of said ferrule overlapping and having surface to surface sealing engagement with the inner side walls respectively of said opposed annular grooves, whereby said ferrule forms a protecting barrier between the inner side of said ring and the fluid in said clearance and constitutes a stop or abutment for said ring to prevent any hammer-likeaction of said ring created by impact loads of fluid in the tube from being imparted to the inner side wall of the annular groove in said tube.

5. A flexible fluid line connection comprising i a tube having a shallow annular groove adjacent one end, the wall of said groove at one side thereof making a small angle with the wall of said tube; a fitting encircling said tube, the inner wall of said fitting having annular clearance with respect to said tube, said fitting having a relatively deep annular groove therein in registry with the groove in said tube, a side wall of said groove adjacent the said wall of said shallow groove making an angle substantially greater than 45 with the inner wall of said fitting; an annular metallic ferrule having angularly IE1 lated' arms; each of which is in substantial surface-to-surface contact with the said wall of one of said grooves, the arm of said ferrule which contacts the said side Wall of said relatively deep groove being substantially shorter than the said side wall thereof; and a ring of resilient material completely filling the annular space defined by said grooves and ferrule. l

6. A thin walled tube having a shallow annular groove thereabout, the wall of said groove at one side thereof making a small angle with the wall of said tube adjacent thereto; a fitting encircling said tube and having annular clearance thereabout, said fitting having an interior annular groove in registry with the groove in said tube; the wall of thegroove in said fitting corresponding to the said wall of the groove in said tube'making an'angle only slightly less than .90 with the wall of said fitting adjacent thereto,

an annular metal ferrule having angularly related arms in surface-to-surface contact with said walls of said grooves and spanning the clearance therebetween, and a resilient ring under compression in said grooves and maintaining the arms of said ferrule in firm contact with said walls the outer diameter of said ferrule being less than'the diameter of the bottom of the groove in said fitting to provide for generally radial movement of said ferrule in said fitting.

'7. Means for establishing a flexible fluid-tight connection with a thin walled tube having an annular groove thereabout, comprising a fitting adapted to encircle the tube and to have annular clearance therewith, said fitting having an internal annular groove in registry with the groove in the tube, a very thin steel ferrule of annular shape adapted to be received in said grooves and to span the clearance between said fitting and the tube at one end of said grooves, said ferrule having angularly related arms each adapted to have substantial surface-to-surface contact with a wall of one of the aforementioned grooves adjacent the said end thereof, and a resilient ring under compression in the space defined by said grooves and adapted to press said ferrule firmly into contact with the said walls the outer diameter of said ferrule being less than the diameter of the bottom of, the. groove in said fitting to provide for generally radial movement of said ferrule in said'fitting. V

8. Means for establishing a flexible fluid-tight connection with a thin walled tube having a shallow annular groove thereabout, comprising a fitting adaptedcto-encircle the tube and to have radial clearance therewith, said fitting having an internal, relatively deep annular groove in registry with the groove in the tube, a resilient ring adapted to be placed under compression in said two grooves, a'very thin steel ferrule of annular shape having angularly related legs in surface-to-surface contact with corresponding side walls of said grooves; the leg in contact with the side Wall of the groove in said fitting being of less outside diameter than the diameter of the bottom of the groove in said fitting, the said side wall of said relatively deep groove forming a large angle with the axis of the fitting to provide for generally radial slidingzmotion of said ferrule thereagainst. 1 v SUMNER WILTSE.

' REFERENCES CITED The following'ireferences are of record in the file of this patent:

UNITED STATES PATENTS I-Lyhes Dec. 5, 1944 

